Lawn scarifier and rake

Abstract

A turf scarifier and raker includes a housing with an elongated upright handle and having suitably positioned wheels designed to permit traversing movements over turf while the operator is in a standing position. The housing has an electric motor positioned in essentially the same plane as a tine assembly driven by the electric motor. The tine assembly has a plurality of tines which extend through an opening at the bottom of the housing. The tines result from a plurality of torsion coil springs having radially extending active ends that are serially threaded on rods arcuately and radially located about a central axle of the tine assembly. The active ends come into contact with the turf when the device is operated. At the same time, the other ends of the springs are inhibited from turning torque, preferably by lying in abutment against the central axle. The tines are arranged along helical paths about the central axle to contribute to a more constant torque resistance to the rotation of the tine assembly by causing the tines along each helical path to successively engage the lawn.

We claim: 
     
       1. A lawn device, comprising: a carriage supported for movement over a lawn;   a handle connected to the carriage and by which the device is manipulated over the lawn by an operator;   a motor supported by the carriage;   a tine assembly mounted in said carriage for rotation therein by said motor about an axis transverse to the direction of travel of the device over the lawn;   said tine assembly comprising a central axle, a plurality of rods supported by and radially spaced from said axle, and a plurality of tine members carried by each rod and defining a cylindrical configuration in use;   said tine members each comprising a portion encircling its respective rod and a tine extending outwardly from said portion, whereby each said tine is deflectable relative to its respective rod; and   said rods being symmetrically and helically positioned about said axle, whereby in use the helix arrangement contributes to a more constant torque resistance to the rotation of said tine assembly by causing the tines along each individual rod to successively engage the lawn.   
     
     
       2. A lawn scarifier and raker device, comprising: a carriage supported for movement over a lawn;   a motor supported by the carriage;   a tine assembly mounted in the carriage for rotation by said motor, and comprising a central shaft, a frame and a plurality of tine members;   said shaft being rotatably supported by the carriage for rotation about an axis transverse to the direction of travel of the device over the lawn;   said frame comprising a plurality of rods supported by and radially spaced from said shaft, each rod defining a helical path about said shaft and having a plurality of said tine members mounted thereon;   each tine member comprising a coil spring threaded on a respective one of said rods, each coil spring terminating in two ends, one of said ends defining a tine extending outwardly from its respective rod and adapted to operate upon the lawn when the device is in use, and the other of said ends defining an arm extending inwardly between said shaft and another of said rods whereby said other end is restrained therebetween and abuts against said shaft when stress is applied against the tine during operation of the device; and   whereby the helical arrangement of each rod contributes to a more constant torque resistance to the rotation of said tine assembly by causing the tines along each individual rod to successively contact the lawn.   
     
     
       3. The device of claim 2, wherein said carriage has an opening through the top and bottom thereof and in which said tine assembly rotates, and further comprising a curved forwardly facing deflector plate supported by said carriage and defining the rear of said opening, whereby in operation debris and/or grass removed from the lawn by said tines is hurled upwardly from said opening and forwardly of the device. 
     
     
       4. The device of claim 3, further comprising a bin catcher releasably attached to said carriage and projecting forwardly thereof to collect the upwardly and forwardly hurled debris and/or grass. 
     
     
       5. The device of claim 2, wherein the carriage has a front and is traversingly supported by wheels on an axle proximate said front, said wheels being shiftable laterally inwardly along said axle whereby the distance between the wheels may be reduced to enable crowns and ridges in the lawn to be ridden and obviate scalping such. 
     
     
       6. The device of claim 2, wherein said motor is an electric motor having its axis substantially in the same horizontal plane as the axis of said tine assembly. 
     
     
       7. The device of claim 2, wherein said tine assembly comprises three helical rods positioned equidistant about the central shaft, upon each of which rods said coil springs are threaded. 
     
     
       8. The device of claim 2, wherein the arm of said other end each coil spring has a bend proximate the coil. 
     
     
       9. A turf scarifier and raker device, comprising: a carriage;   a tine assembly rotatably mounted in the carriage; and   a prime mover operatively connected to the tine assembly for rotating the latter;   said tine assembly comprising:   a plurality of stacked axially aligned carrier means;   means for securing said stack whereby the stack may be rotated in unison when said device is operated;   each of said carrier means having at least one outwardly facing open pocket;   a plurality of coil springs having an elongated active end and a reactive end; and   means in said pocket for retaining said coil spring whereby the said elongated active end extends radially beyond said open pocket whereby said active ends engage the turf when said device is operated.   
     
     
       10. The device of claim 9, wherein the carrier means has three outwardly facing open pockets. 
     
     
       11. The device of claim 10, wherein each of said carrier means is positioned so as to cause the pockets of one carrier means to be offset by a minor angle from the pockets of the next adjacent carrier means, said offset being incremental and progressive to subtend on the part of the plurality of carrier means a relatively uniform continuing angle whereby the pockets and the elongated active ends of the coil springs define a helix arrangement. 
     
     
       12. The device of claim 11, wherein the means in said pocket for retaining a coil spring of one carrier means is adapted to be in operative cooperation with an adjacent carrier means to retain its relative position in said stack. 
     
     
       13. The device of claim 12, wherein each of the carrier means has a central bore and each is mounted on an axle. 
     
     
       14. In a lawn scarifier and rake, the combination of a carriage and means for longitudinally moving the carriage across the lawn, a shaft rotatably journaled in the carriage along an axis transverse to the longitudinal movement of the carriage, a plurality of respective rods spaced radially from the shaft, means for rotating the rods in unison with the shaft and about the axis of the shaft as an integral assembly, each of the rods being disposed along a helical angle with respect to the shaft, and a plurality of coil springs serially threaded axially on each rod and carried thereby, each of the springs having a pair of ends including an active end and a passive end respectively projecting radially of the rod, the active end being formed as a tine for engaging the lawn during operation, and the passive end being reactively deflected against the shaft substantially in tangential abutment thereto when stress is applied to the tine during operation, whereby the helical angle of the rods contributes to a more constant torque resistance to the rotation of said assembly by causing the tines along each rod to successively engage the lawn. 
     
     
       15. The combination of claim 14, wherein three rods are disposed around the shaft, each rod passing helically through an angle of substantially 120 degrees over its length, and wherein the first tine in any one row is in substantially the same axial plane as the last tine in the preceding row. 
     
     
       16. In a lawn scarifier and rake, the combination of a carriage and means for longitudinally moving the carriage across the lawn, a shaft rotatably journaled in the carriage along an axis transverse to the longitudinal movement of the carriage, a motor on the carriage for driving the shaft, three rods each spaced radially of the shaft and substantially equidistant to each other, means for rotating the rods in unison with the shaft and about the axis of the shaft as an integral assembly, each of the rods passing helically through an angle of substantially 120 degrees over its length, and a plurality of coil springs mounted on each rod in substantial axial abutting relationship to each other, and each of the springs having a radially-projecting end portion formed as a tine for engaging the lawn during operation, the first tine in any one row being in substantially the same axial plane as the last tine in the prededing row, thus preceding a substantially constant torque resistance to the rotation of said assembly by causing the tines along each individual rod to make contact with the lawn in succession. 
     
     
       17. A lawn device, comprising: a carriage supported for movement over a lawn and having an opening in the top thereof;   a handle connected to the carriage and by which the device is manipulated over the lawn by an operator;   a motor supported by the carriage;   a tine assembly mounted in said carriage in communication with said opening for rotation by said motor about an axis transverse to the direction of travel of the device over the lawn, the direction of rotation of said tine assembly assisting forward propulsion of said device;   said tine assembly comprising at least one rod spaced radially from and defining a helical path about said axis, and a plurality of tine members carried by said rod, each tine member having a portion encircling said rod with a tine extending outwardly from said portion and adapted to operate upon the lawn when the device is in use, whereby said helical path contributes to a more constant torque resistance by allowing the tines on said rod to successively operate upon the lawn; and   a forwardly facing deflector plate supported by said carriage at the rear of said opening, whereby in operation debris and/or grass removed from the lawn by said tines is hurled upwardly through said opening and forwardly of said carriage.   
     
     
       18. The lawn device of claim 17, wherein said tine assembly includes a central shaft mounted in said carriage for rotation about said axis, and support members attached to said shaft and supporting said rod in spaced relation thereto. 
     
     
       19. The lawn device of claim 18, wherein said portion of the tine members has an arm extending inwardly of the tine assembly and abutting against said shaft when stress is applied against the tine during operation of the device. 
     
     
       20. The lawn device of claim 17, wherein said deflector plate is arcuate and in close relationship to said tine assembly, and further comprising a bin catcher releasably attached to said carriage and projecting forwardly thereof for collecting the forwardly directed debris and/or grass. 
     
     
       21. The lawn device of claim 17, wherein said tine assembly has at least two of said helical rods carrying tine members, and said rods are supported on said shaft by at least three said support members, one at each end of the tine assembly and one intermediate the length thereof. 
     
     
       22. The lawn device of claim 17, wherein the motor is electrically powered and is mounted in a closed housing in said carriage rearwardly of said forwardly facing deflector plate. 
     
     
       23. The lawn device of claim 17, wherein rotatable members are rotatably mounted at the front of said carriage, and a roller is rotatably mounted at the rear of said carriage, whereby said carriage is supported for movement over the lawn. 
     
     
       24. The lawn device of claim 23, wherein said roller is adjustably mounted to control the height of said carriage above the grass of the lawn between two positions, one in which said tines scarify the surface and another in which said tines are clear of the ground.